diff options
| author |   Christoph Hellwig <hch@lst.de> | 2022-04-15 06:52:58 +0200 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2022-04-17 19:50:02 -0600 |
| commit | c22198e78d523c8fa079bbb70b2523bb6aa51849 (patch) | |
| tree | b54b081561405d3e1f26da56451230594e6c6af8 | |
| parent | block: decouple REQ_OP_SECURE_ERASE from REQ_OP_DISCARD (diff) | |
| download | linux-dev-c22198e78d523c8fa079bbb70b2523bb6aa51849.tar.xz linux-dev-c22198e78d523c8fa079bbb70b2523bb6aa51849.zip | |
direct-io: remove random prefetches
Randomly poking into block device internals for manual prefetches isn't
exactly a very maintainable thing to do. And none of the performance
critical direct I/O implementations still use this library function
anyway, so just drop it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220415045258.199825-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | fs/direct-io.c | 32 |
1 files changed, 4 insertions, 28 deletions
diff --git a/fs/direct-io.c b/fs/direct-io.c index aef06e607b40..840752006f60 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -1115,11 +1115,10 @@ static inline int drop_refcount(struct dio *dio) * individual fields and will generate much worse code. This is important * for the whole file. */ -static inline ssize_t -do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode, - struct block_device *bdev, struct iov_iter *iter, - get_block_t get_block, dio_iodone_t end_io, - dio_submit_t submit_io, int flags) +ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode, + struct block_device *bdev, struct iov_iter *iter, + get_block_t get_block, dio_iodone_t end_io, + dio_submit_t submit_io, int flags) { unsigned i_blkbits = READ_ONCE(inode->i_blkbits); unsigned blkbits = i_blkbits; @@ -1334,29 +1333,6 @@ fail_dio: kmem_cache_free(dio_cache, dio); return retval; } - -ssize_t __blockdev_direct_IO(struct kiocb *iocb, struct inode *inode, - struct block_device *bdev, struct iov_iter *iter, - get_block_t get_block, - dio_iodone_t end_io, dio_submit_t submit_io, - int flags) -{ - /* - * The block device state is needed in the end to finally - * submit everything. Since it's likely to be cache cold - * prefetch it here as first thing to hide some of the - * latency. - * - * Attempt to prefetch the pieces we likely need later. - */ - prefetch(&bdev->bd_disk->part_tbl); - prefetch(bdev->bd_disk->queue); - prefetch((char *)bdev->bd_disk->queue + SMP_CACHE_BYTES); - - return do_blockdev_direct_IO(iocb, inode, bdev, iter, get_block, - end_io, submit_io, flags); -} - EXPORT_SYMBOL(__blockdev_direct_IO); static __init int dio_init(void) |